Warden M K, Young W S
Laboratory of Cell Biology, National Institute of Mental Health, Bethesda, Maryland 20892.
J Comp Neurol. 1988 Jun 1;272(1):90-113. doi: 10.1002/cne.902720107.
The family of tachykinins includes the neuropeptides substance P, neurokinin A, and neurokinin B. The distribution of substance P in the central nervous system has been studied immunohistochemically but the lack of specific antibodies has prevented similar studies of neurokinin B. Recent molecular genetics techniques have revealed the sequences for the complementary DNAs that code for the substance P and neurokinin B precursors. These results have permitted the design of specific probes to differentiate between substance P and neurokinin B transcripts by using in situ hybridization histochemistry. Our probes, 48-base synthetic oligodeoxynucleotides labeled with 35S revealed extensive and distinct patterns of cell labeling for both substance P and neurokinin B throughout the rat central nervous system. The distribution of substance-P-mRNA-containing cells that we observed confirmed and extended previous immunocytochemical descriptions. Cells containing transcripts for either tachykinin were present in the neocortex, hippocampus, olfactory bulb and associated areas, caudate-putamen, hypothalamus, medial habenula, superior colliculus, central gray, and dorsal horn of the spinal cord. However, their distributions within these areas were usually quite different. Other areas contained only one tachykinin cell type: e.g., the nucleus of the lateral olfactory tract contained only neurokinin B cells whereas the raphe nuclei had only substance P cells. This study demonstrates the sensitivity and specificity of in situ hybridization histochemistry for mapping peptidergic neurons and lays the foundation for further investigations of the roles of these two tachykinins in the central nervous system.
速激肽家族包括神经肽P物质、神经激肽A和神经激肽B。P物质在中枢神经系统中的分布已通过免疫组织化学方法进行了研究，但由于缺乏特异性抗体，无法对神经激肽B进行类似研究。最近的分子遗传学技术揭示了编码P物质和神经激肽B前体的互补DNA序列。这些结果使得能够设计特异性探针，通过原位杂交组织化学来区分P物质和神经激肽B的转录本。我们的探针是用35S标记的48个碱基的合成寡脱氧核苷酸，在整个大鼠中枢神经系统中揭示了P物质和神经激肽B广泛且独特的细胞标记模式。我们观察到的含P物质mRNA的细胞分布证实并扩展了先前的免疫细胞化学描述。含有任何一种速激肽转录本的细胞存在于新皮层、海马体、嗅球及相关区域、尾状核-壳核、下丘脑、内侧缰核、上丘、中央灰质和脊髓背角。然而，它们在这些区域内的分布通常有很大差异。其他区域只含有一种速激肽细胞类型：例如，外侧嗅束核只含有神经激肽B细胞，而中缝核只含有P物质细胞。这项研究证明了原位杂交组织化学在绘制肽能神经元图谱方面的敏感性和特异性，并为进一步研究这两种速激肽在中枢神经系统中的作用奠定了基础。
